Prove that the symmetry (or antisymmetry) of a tensor is preserved by Lorentz transformation (that is: if tμvis symmetric, show thatt¯μv is also symmetric, and likewise for antisymmetric).

Short Answer

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The symmetry (or antisymmetry) of a tensor is preserved by Lorentz transformation.

Step by step solution

01

Expression for the property of symmetric and antisymmetric tensor:

Write the property of the symmetric tensor.

tμv=t

Write the property of an anti-symmetric tensor.

tμv=-t

Here, a negative sign for anti-symmetric tensor.

02

Determine the symmetry or antisymmetry of a tensor:

ConsidertKλ=ΛμKΛvλtμv

Here,Λ is the Lorentz transformation matrix.

Sinceμ and v both are summed from0 to 3, both the values can be interchanged.

Hence, the above equation becomes,

tλK=ΛμKΛμKtμvtλK=ΛvλΛμKtvμtλK=ΛμKΛμλ(tμv)tλK=±tKλ

Therefore, the symmetry (or antisymmetry) of a tensor is preserved by Lorentz transformation.

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